Effect of Stratification and Gibberellin on Seed Germination in Ginkgo biloba

Abstract

WEST, W. CHARLES, FRANCESCA J. FRATTARELLI, ancd KAREN J. RusSIN (The City College, New York, N.Y. 10031). Effect of stratification ancd gibberellin on seed germinationi in Ginkgo biloba. Bull. Toirey Bot. Club 97: 380-384. 1970.-The effects of stratification ancd exogenous gibberellic acid on seed germination in Ginkgo biloba were followed for a 12-week period. Most nonstratified seeds either remain dormant or decompose during this period, while nearly 100% of stratified seeds germinate within 7-10 weeks. Reilloval of the hard portion of the seed coat produces oiily a slight enhancement in germination of noiistratified seeds. Exogenous application of gibberellic acid to nonstratified seeds enhaniees ger mination to a level that approaches that of stratified seeds. Barley endosperm bioassay data of ethyl acetate extractable gibberellins froim Ginkgo embryos indicate that stratified embryos contain approximately 100 times more GA, equivalents thani nionstratified embryos. It is coneluded that stratificationi anid gibberellin metabolism are related in the germination of Ginkgo seeds, anid that exogenious GA3 will largely substitute for stratification in lionstratified seeds to promote germ-iinationi.